4D v13.4
Before selection
- 4D Language Reference
-
- Selection
-
- ALL RECORDS
- APPLY TO SELECTION
- Before selection
- DELETE SELECTION
- DISPLAY SELECTION
- Displayed line number
- End selection
- FIRST RECORD
- GET HIGHLIGHTED RECORDS
- GOTO SELECTED RECORD
- HIGHLIGHT RECORDS
- LAST RECORD
- MODIFY SELECTION
- NEXT RECORD
- ONE RECORD SELECT
- PREVIOUS RECORD
- Records in selection
- REDUCE SELECTION
- SCAN INDEX
- Selected record number
- TRUNCATE TABLE
Before selection
| Before selection {( aTable )} -> Function result | ||||||||
| Parameter | Type | Description | ||||||
| aTable | Table |
|
Table for which to test if record pointer is before the first selected record, or Default table, if omitted | |||||
| Function result | Boolean |
|
Yes (TRUE) or No (FALSE) | |||||
Before selection returns TRUE when the current record pointer is before the first record of the current selection of table.Before selection is commonly used to check whether or not PREVIOUS RECORD has moved the current record pointer before the first record. If the current selection is empty, Before selection returns TRUE.
To move the current record pointer back into the selection, use FIRST RECORD, LAST RECORD or GOTO SELECTED RECORD. NEXT RECORD does not move the pointer back into the selection.
Before selection also returns TRUE in the first header when a report is being printed with PRINT SELECTION or from the Print menu. You can use the following code to test for the first header and print a special header for the first page:
` Method of a form being used as output form for a summary report
$vpFormTable:=Current form table
Case of
` ...
:(Form event=On Header)
` A header area is about to be printed
Case of
:(Before selection($vpFormTable->))
` Code for the first break header goes here
` ...
End case
End caseThis form method is used during the printing of a report. It sets a variable, vTitle, to print in the Header area on the first page:
` [Finances];"Summary" Form Method
Case of
` ...
:(Form event=On Header)
Case of
:(Before selection([Finances))
vTitle:="Corporate Report 1997" ` Set the title for the first page
Else
vTitle:="" ` Clear the title for all other pages
End case
End case
Product: 4D
Theme: Selection
Number:
198
Created: < 4D v6
End selection
FIRST RECORD
Form event
PREVIOUS RECORD
PRINT SELECTION
